Using PHP Dom to change href

Hi all,

   I have a main webpage in PHP and it calls an AJAX page.  In that AJAX page I have it doing a bunch of SQL queries.  From one of the queries I get a result that I need to use in an HREF statement that has to dynamically change anytime the AJAX script is called.  I used

$dom = new DOMDocument();

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on the main page and this in the AJAX page

$dom->getElementById('ACGFM')->setAttribute('href', '' . $q2);

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But I'm getting an error "call to a member function getElementById() on a non-object"


Thanks - Zack
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Marco GasiFreelancerCommented:
"In the AJAX page"? How AJAX page knows about $dom? If you create an object in a page, this object is available only in that page unless you don't serialize it to pass it to another page (or if you don't use JSON to do so.
But if you're using AJAX, you can just change the haref within the javascript using the returned value from the AJAX page.
Anyway, I'd need to see more code from the main page, from the AJAX page and from the javascript  you're using to make Ajax call.
Julian HansenCommented:
The problem here is you are mixing PHP (server side) and Javascript (Clinet Side)

Your PHP document does not have access to the page that initiated the AJAX call.

To do what you want to do you have to make the AJAX call from your client side page to your PHP script which then returns the requested value and then using JavaScript in your AJAX success call you need to set the HREF of the desired element.

This simple example demonstrates the concept.
<!doctype html>
  Data <input type="text" name="linkfield" /> <br/>
  <input type="submit" />
<a href="#" id="target">URL</a>
<script src=""></script>

<!-- Latest compiled and minified JavaScript -->
<script src="js/bootstrap.js"></script>
<script type="text/javascript">
$(function() {
  $('form').submit(function() {
      url: 'geturl.php',
      data: $(this).serialize(),
      type: 'POST',
      success:function (resp) {
        if (resp != '') {
          $('#target').attr('href', resp);
    return false;


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$linkfield = empty($_POST['linkfield']) ? '' : $_POST['linkfield'];
echo $linkfield;

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The code takes what you enter AJAX's it to the PHP script which echo's it back to the script which then changes the URL link.

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Ray PaseurCommented:
zack4x4Author Commented:
Julian HansenCommented:
You are welcome.
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